The Best Digital Campaign Ever?

Shooting around a couple of ideas for topics in the Internet Show, the topic went around to what is the single best digital marketing campaign out there?

Here’s some to get us started:

The Nike Running Campaign

Old Spice Campaign (talked about this one here)

Tipp-Ex Campaign (also wrote a blog post on this campaign here)

Evian Campaign

But what exactly makes a digital campaign effective? The sales that follow? The effect on customer engagement? How funny / sharable it is?

The consumer side tells me its the funny / how sharable the content is. However, I’ve never myself bought any of those above listed products before.

What do you think are the best digital marketing campaigns ever?